Lehto MT and Sharom FJ (2002). Proximity of the protein moiety of a GPI-anchored protein to the membrane surface: a FRET study. Biochemistry 41, 8368-76; Amir D and Haas E (1987). Estimation of intramolecular distance distributions in bovine pancreatic trypsin inhibitor by site-specific labeling and nonradiative excitation energy-transfer measurements. Biochemistry 26, 2162-75.